xref: /openbmc/linux/drivers/mtd/mtdpart.c (revision a1e58bbd)
1 /*
2  * Simple MTD partitioning layer
3  *
4  * (C) 2000 Nicolas Pitre <nico@cam.org>
5  *
6  * This code is GPL
7  *
8  * $Id: mtdpart.c,v 1.55 2005/11/07 11:14:20 gleixner Exp $
9  *
10  * 	02-21-2002	Thomas Gleixner <gleixner@autronix.de>
11  *			added support for read_oob, write_oob
12  */
13 
14 #include <linux/module.h>
15 #include <linux/types.h>
16 #include <linux/kernel.h>
17 #include <linux/slab.h>
18 #include <linux/list.h>
19 #include <linux/kmod.h>
20 #include <linux/mtd/mtd.h>
21 #include <linux/mtd/partitions.h>
22 #include <linux/mtd/compatmac.h>
23 
24 /* Our partition linked list */
25 static LIST_HEAD(mtd_partitions);
26 
27 /* Our partition node structure */
28 struct mtd_part {
29 	struct mtd_info mtd;
30 	struct mtd_info *master;
31 	u_int32_t offset;
32 	int index;
33 	struct list_head list;
34 	int registered;
35 };
36 
37 /*
38  * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
39  * the pointer to that structure with this macro.
40  */
41 #define PART(x)  ((struct mtd_part *)(x))
42 
43 
44 /*
45  * MTD methods which simply translate the effective address and pass through
46  * to the _real_ device.
47  */
48 
49 static int part_read (struct mtd_info *mtd, loff_t from, size_t len,
50 			size_t *retlen, u_char *buf)
51 {
52 	struct mtd_part *part = PART(mtd);
53 	int res;
54 
55 	if (from >= mtd->size)
56 		len = 0;
57 	else if (from + len > mtd->size)
58 		len = mtd->size - from;
59 	res = part->master->read (part->master, from + part->offset,
60 				   len, retlen, buf);
61 	if (unlikely(res)) {
62 		if (res == -EUCLEAN)
63 			mtd->ecc_stats.corrected++;
64 		if (res == -EBADMSG)
65 			mtd->ecc_stats.failed++;
66 	}
67 	return res;
68 }
69 
70 static int part_point (struct mtd_info *mtd, loff_t from, size_t len,
71 			size_t *retlen, u_char **buf)
72 {
73 	struct mtd_part *part = PART(mtd);
74 	if (from >= mtd->size)
75 		len = 0;
76 	else if (from + len > mtd->size)
77 		len = mtd->size - from;
78 	return part->master->point (part->master, from + part->offset,
79 				    len, retlen, buf);
80 }
81 
82 static void part_unpoint (struct mtd_info *mtd, u_char *addr, loff_t from, size_t len)
83 {
84 	struct mtd_part *part = PART(mtd);
85 
86 	part->master->unpoint (part->master, addr, from + part->offset, len);
87 }
88 
89 static int part_read_oob(struct mtd_info *mtd, loff_t from,
90 			 struct mtd_oob_ops *ops)
91 {
92 	struct mtd_part *part = PART(mtd);
93 	int res;
94 
95 	if (from >= mtd->size)
96 		return -EINVAL;
97 	if (ops->datbuf && from + ops->len > mtd->size)
98 		return -EINVAL;
99 	res = part->master->read_oob(part->master, from + part->offset, ops);
100 
101 	if (unlikely(res)) {
102 		if (res == -EUCLEAN)
103 			mtd->ecc_stats.corrected++;
104 		if (res == -EBADMSG)
105 			mtd->ecc_stats.failed++;
106 	}
107 	return res;
108 }
109 
110 static int part_read_user_prot_reg (struct mtd_info *mtd, loff_t from, size_t len,
111 			size_t *retlen, u_char *buf)
112 {
113 	struct mtd_part *part = PART(mtd);
114 	return part->master->read_user_prot_reg (part->master, from,
115 					len, retlen, buf);
116 }
117 
118 static int part_get_user_prot_info (struct mtd_info *mtd,
119 				    struct otp_info *buf, size_t len)
120 {
121 	struct mtd_part *part = PART(mtd);
122 	return part->master->get_user_prot_info (part->master, buf, len);
123 }
124 
125 static int part_read_fact_prot_reg (struct mtd_info *mtd, loff_t from, size_t len,
126 			size_t *retlen, u_char *buf)
127 {
128 	struct mtd_part *part = PART(mtd);
129 	return part->master->read_fact_prot_reg (part->master, from,
130 					len, retlen, buf);
131 }
132 
133 static int part_get_fact_prot_info (struct mtd_info *mtd,
134 				    struct otp_info *buf, size_t len)
135 {
136 	struct mtd_part *part = PART(mtd);
137 	return part->master->get_fact_prot_info (part->master, buf, len);
138 }
139 
140 static int part_write (struct mtd_info *mtd, loff_t to, size_t len,
141 			size_t *retlen, const u_char *buf)
142 {
143 	struct mtd_part *part = PART(mtd);
144 	if (!(mtd->flags & MTD_WRITEABLE))
145 		return -EROFS;
146 	if (to >= mtd->size)
147 		len = 0;
148 	else if (to + len > mtd->size)
149 		len = mtd->size - to;
150 	return part->master->write (part->master, to + part->offset,
151 				    len, retlen, buf);
152 }
153 
154 static int part_panic_write (struct mtd_info *mtd, loff_t to, size_t len,
155 			size_t *retlen, const u_char *buf)
156 {
157 	struct mtd_part *part = PART(mtd);
158 	if (!(mtd->flags & MTD_WRITEABLE))
159 		return -EROFS;
160 	if (to >= mtd->size)
161 		len = 0;
162 	else if (to + len > mtd->size)
163 		len = mtd->size - to;
164 	return part->master->panic_write (part->master, to + part->offset,
165 				    len, retlen, buf);
166 }
167 
168 static int part_write_oob(struct mtd_info *mtd, loff_t to,
169 			 struct mtd_oob_ops *ops)
170 {
171 	struct mtd_part *part = PART(mtd);
172 
173 	if (!(mtd->flags & MTD_WRITEABLE))
174 		return -EROFS;
175 
176 	if (to >= mtd->size)
177 		return -EINVAL;
178 	if (ops->datbuf && to + ops->len > mtd->size)
179 		return -EINVAL;
180 	return part->master->write_oob(part->master, to + part->offset, ops);
181 }
182 
183 static int part_write_user_prot_reg (struct mtd_info *mtd, loff_t from, size_t len,
184 			size_t *retlen, u_char *buf)
185 {
186 	struct mtd_part *part = PART(mtd);
187 	return part->master->write_user_prot_reg (part->master, from,
188 					len, retlen, buf);
189 }
190 
191 static int part_lock_user_prot_reg (struct mtd_info *mtd, loff_t from, size_t len)
192 {
193 	struct mtd_part *part = PART(mtd);
194 	return part->master->lock_user_prot_reg (part->master, from, len);
195 }
196 
197 static int part_writev (struct mtd_info *mtd,  const struct kvec *vecs,
198 			 unsigned long count, loff_t to, size_t *retlen)
199 {
200 	struct mtd_part *part = PART(mtd);
201 	if (!(mtd->flags & MTD_WRITEABLE))
202 		return -EROFS;
203 	return part->master->writev (part->master, vecs, count,
204 					to + part->offset, retlen);
205 }
206 
207 static int part_erase (struct mtd_info *mtd, struct erase_info *instr)
208 {
209 	struct mtd_part *part = PART(mtd);
210 	int ret;
211 	if (!(mtd->flags & MTD_WRITEABLE))
212 		return -EROFS;
213 	if (instr->addr >= mtd->size)
214 		return -EINVAL;
215 	instr->addr += part->offset;
216 	ret = part->master->erase(part->master, instr);
217 	if (ret) {
218 		if (instr->fail_addr != 0xffffffff)
219 			instr->fail_addr -= part->offset;
220 		instr->addr -= part->offset;
221 	}
222 	return ret;
223 }
224 
225 void mtd_erase_callback(struct erase_info *instr)
226 {
227 	if (instr->mtd->erase == part_erase) {
228 		struct mtd_part *part = PART(instr->mtd);
229 
230 		if (instr->fail_addr != 0xffffffff)
231 			instr->fail_addr -= part->offset;
232 		instr->addr -= part->offset;
233 	}
234 	if (instr->callback)
235 		instr->callback(instr);
236 }
237 EXPORT_SYMBOL_GPL(mtd_erase_callback);
238 
239 static int part_lock (struct mtd_info *mtd, loff_t ofs, size_t len)
240 {
241 	struct mtd_part *part = PART(mtd);
242 	if ((len + ofs) > mtd->size)
243 		return -EINVAL;
244 	return part->master->lock(part->master, ofs + part->offset, len);
245 }
246 
247 static int part_unlock (struct mtd_info *mtd, loff_t ofs, size_t len)
248 {
249 	struct mtd_part *part = PART(mtd);
250 	if ((len + ofs) > mtd->size)
251 		return -EINVAL;
252 	return part->master->unlock(part->master, ofs + part->offset, len);
253 }
254 
255 static void part_sync(struct mtd_info *mtd)
256 {
257 	struct mtd_part *part = PART(mtd);
258 	part->master->sync(part->master);
259 }
260 
261 static int part_suspend(struct mtd_info *mtd)
262 {
263 	struct mtd_part *part = PART(mtd);
264 	return part->master->suspend(part->master);
265 }
266 
267 static void part_resume(struct mtd_info *mtd)
268 {
269 	struct mtd_part *part = PART(mtd);
270 	part->master->resume(part->master);
271 }
272 
273 static int part_block_isbad (struct mtd_info *mtd, loff_t ofs)
274 {
275 	struct mtd_part *part = PART(mtd);
276 	if (ofs >= mtd->size)
277 		return -EINVAL;
278 	ofs += part->offset;
279 	return part->master->block_isbad(part->master, ofs);
280 }
281 
282 static int part_block_markbad (struct mtd_info *mtd, loff_t ofs)
283 {
284 	struct mtd_part *part = PART(mtd);
285 	int res;
286 
287 	if (!(mtd->flags & MTD_WRITEABLE))
288 		return -EROFS;
289 	if (ofs >= mtd->size)
290 		return -EINVAL;
291 	ofs += part->offset;
292 	res = part->master->block_markbad(part->master, ofs);
293 	if (!res)
294 		mtd->ecc_stats.badblocks++;
295 	return res;
296 }
297 
298 /*
299  * This function unregisters and destroy all slave MTD objects which are
300  * attached to the given master MTD object.
301  */
302 
303 int del_mtd_partitions(struct mtd_info *master)
304 {
305 	struct list_head *node;
306 	struct mtd_part *slave;
307 
308 	for (node = mtd_partitions.next;
309 	     node != &mtd_partitions;
310 	     node = node->next) {
311 		slave = list_entry(node, struct mtd_part, list);
312 		if (slave->master == master) {
313 			struct list_head *prev = node->prev;
314 			__list_del(prev, node->next);
315 			if(slave->registered)
316 				del_mtd_device(&slave->mtd);
317 			kfree(slave);
318 			node = prev;
319 		}
320 	}
321 
322 	return 0;
323 }
324 
325 /*
326  * This function, given a master MTD object and a partition table, creates
327  * and registers slave MTD objects which are bound to the master according to
328  * the partition definitions.
329  * (Q: should we register the master MTD object as well?)
330  */
331 
332 int add_mtd_partitions(struct mtd_info *master,
333 		       const struct mtd_partition *parts,
334 		       int nbparts)
335 {
336 	struct mtd_part *slave;
337 	u_int32_t cur_offset = 0;
338 	int i;
339 
340 	printk (KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
341 
342 	for (i = 0; i < nbparts; i++) {
343 
344 		/* allocate the partition structure */
345 		slave = kzalloc (sizeof(*slave), GFP_KERNEL);
346 		if (!slave) {
347 			printk ("memory allocation error while creating partitions for \"%s\"\n",
348 				master->name);
349 			del_mtd_partitions(master);
350 			return -ENOMEM;
351 		}
352 		list_add(&slave->list, &mtd_partitions);
353 
354 		/* set up the MTD object for this partition */
355 		slave->mtd.type = master->type;
356 		slave->mtd.flags = master->flags & ~parts[i].mask_flags;
357 		slave->mtd.size = parts[i].size;
358 		slave->mtd.writesize = master->writesize;
359 		slave->mtd.oobsize = master->oobsize;
360 		slave->mtd.oobavail = master->oobavail;
361 		slave->mtd.subpage_sft = master->subpage_sft;
362 
363 		slave->mtd.name = parts[i].name;
364 		slave->mtd.owner = master->owner;
365 
366 		slave->mtd.read = part_read;
367 		slave->mtd.write = part_write;
368 
369 		if (master->panic_write)
370 			slave->mtd.panic_write = part_panic_write;
371 
372 		if(master->point && master->unpoint){
373 			slave->mtd.point = part_point;
374 			slave->mtd.unpoint = part_unpoint;
375 		}
376 
377 		if (master->read_oob)
378 			slave->mtd.read_oob = part_read_oob;
379 		if (master->write_oob)
380 			slave->mtd.write_oob = part_write_oob;
381 		if(master->read_user_prot_reg)
382 			slave->mtd.read_user_prot_reg = part_read_user_prot_reg;
383 		if(master->read_fact_prot_reg)
384 			slave->mtd.read_fact_prot_reg = part_read_fact_prot_reg;
385 		if(master->write_user_prot_reg)
386 			slave->mtd.write_user_prot_reg = part_write_user_prot_reg;
387 		if(master->lock_user_prot_reg)
388 			slave->mtd.lock_user_prot_reg = part_lock_user_prot_reg;
389 		if(master->get_user_prot_info)
390 			slave->mtd.get_user_prot_info = part_get_user_prot_info;
391 		if(master->get_fact_prot_info)
392 			slave->mtd.get_fact_prot_info = part_get_fact_prot_info;
393 		if (master->sync)
394 			slave->mtd.sync = part_sync;
395 		if (!i && master->suspend && master->resume) {
396 				slave->mtd.suspend = part_suspend;
397 				slave->mtd.resume = part_resume;
398 		}
399 		if (master->writev)
400 			slave->mtd.writev = part_writev;
401 		if (master->lock)
402 			slave->mtd.lock = part_lock;
403 		if (master->unlock)
404 			slave->mtd.unlock = part_unlock;
405 		if (master->block_isbad)
406 			slave->mtd.block_isbad = part_block_isbad;
407 		if (master->block_markbad)
408 			slave->mtd.block_markbad = part_block_markbad;
409 		slave->mtd.erase = part_erase;
410 		slave->master = master;
411 		slave->offset = parts[i].offset;
412 		slave->index = i;
413 
414 		if (slave->offset == MTDPART_OFS_APPEND)
415 			slave->offset = cur_offset;
416 		if (slave->offset == MTDPART_OFS_NXTBLK) {
417 			slave->offset = cur_offset;
418 			if ((cur_offset % master->erasesize) != 0) {
419 				/* Round up to next erasesize */
420 				slave->offset = ((cur_offset / master->erasesize) + 1) * master->erasesize;
421 				printk(KERN_NOTICE "Moving partition %d: "
422 				       "0x%08x -> 0x%08x\n", i,
423 				       cur_offset, slave->offset);
424 			}
425 		}
426 		if (slave->mtd.size == MTDPART_SIZ_FULL)
427 			slave->mtd.size = master->size - slave->offset;
428 		cur_offset = slave->offset + slave->mtd.size;
429 
430 		printk (KERN_NOTICE "0x%08x-0x%08x : \"%s\"\n", slave->offset,
431 			slave->offset + slave->mtd.size, slave->mtd.name);
432 
433 		/* let's do some sanity checks */
434 		if (slave->offset >= master->size) {
435 				/* let's register it anyway to preserve ordering */
436 			slave->offset = 0;
437 			slave->mtd.size = 0;
438 			printk ("mtd: partition \"%s\" is out of reach -- disabled\n",
439 				parts[i].name);
440 		}
441 		if (slave->offset + slave->mtd.size > master->size) {
442 			slave->mtd.size = master->size - slave->offset;
443 			printk ("mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#x\n",
444 				parts[i].name, master->name, slave->mtd.size);
445 		}
446 		if (master->numeraseregions>1) {
447 			/* Deal with variable erase size stuff */
448 			int i;
449 			struct mtd_erase_region_info *regions = master->eraseregions;
450 
451 			/* Find the first erase regions which is part of this partition. */
452 			for (i=0; i < master->numeraseregions && slave->offset >= regions[i].offset; i++)
453 				;
454 
455 			for (i--; i < master->numeraseregions && slave->offset + slave->mtd.size > regions[i].offset; i++) {
456 				if (slave->mtd.erasesize < regions[i].erasesize) {
457 					slave->mtd.erasesize = regions[i].erasesize;
458 				}
459 			}
460 		} else {
461 			/* Single erase size */
462 			slave->mtd.erasesize = master->erasesize;
463 		}
464 
465 		if ((slave->mtd.flags & MTD_WRITEABLE) &&
466 		    (slave->offset % slave->mtd.erasesize)) {
467 			/* Doesn't start on a boundary of major erase size */
468 			/* FIXME: Let it be writable if it is on a boundary of _minor_ erase size though */
469 			slave->mtd.flags &= ~MTD_WRITEABLE;
470 			printk ("mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
471 				parts[i].name);
472 		}
473 		if ((slave->mtd.flags & MTD_WRITEABLE) &&
474 		    (slave->mtd.size % slave->mtd.erasesize)) {
475 			slave->mtd.flags &= ~MTD_WRITEABLE;
476 			printk ("mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
477 				parts[i].name);
478 		}
479 
480 		slave->mtd.ecclayout = master->ecclayout;
481 		if (master->block_isbad) {
482 			uint32_t offs = 0;
483 
484 			while(offs < slave->mtd.size) {
485 				if (master->block_isbad(master,
486 							offs + slave->offset))
487 					slave->mtd.ecc_stats.badblocks++;
488 				offs += slave->mtd.erasesize;
489 			}
490 		}
491 
492 		if(parts[i].mtdp)
493 		{	/* store the object pointer (caller may or may not register it */
494 			*parts[i].mtdp = &slave->mtd;
495 			slave->registered = 0;
496 		}
497 		else
498 		{
499 			/* register our partition */
500 			add_mtd_device(&slave->mtd);
501 			slave->registered = 1;
502 		}
503 	}
504 
505 	return 0;
506 }
507 
508 EXPORT_SYMBOL(add_mtd_partitions);
509 EXPORT_SYMBOL(del_mtd_partitions);
510 
511 static DEFINE_SPINLOCK(part_parser_lock);
512 static LIST_HEAD(part_parsers);
513 
514 static struct mtd_part_parser *get_partition_parser(const char *name)
515 {
516 	struct list_head *this;
517 	void *ret = NULL;
518 	spin_lock(&part_parser_lock);
519 
520 	list_for_each(this, &part_parsers) {
521 		struct mtd_part_parser *p = list_entry(this, struct mtd_part_parser, list);
522 
523 		if (!strcmp(p->name, name) && try_module_get(p->owner)) {
524 			ret = p;
525 			break;
526 		}
527 	}
528 	spin_unlock(&part_parser_lock);
529 
530 	return ret;
531 }
532 
533 int register_mtd_parser(struct mtd_part_parser *p)
534 {
535 	spin_lock(&part_parser_lock);
536 	list_add(&p->list, &part_parsers);
537 	spin_unlock(&part_parser_lock);
538 
539 	return 0;
540 }
541 
542 int deregister_mtd_parser(struct mtd_part_parser *p)
543 {
544 	spin_lock(&part_parser_lock);
545 	list_del(&p->list);
546 	spin_unlock(&part_parser_lock);
547 	return 0;
548 }
549 
550 int parse_mtd_partitions(struct mtd_info *master, const char **types,
551 			 struct mtd_partition **pparts, unsigned long origin)
552 {
553 	struct mtd_part_parser *parser;
554 	int ret = 0;
555 
556 	for ( ; ret <= 0 && *types; types++) {
557 		parser = get_partition_parser(*types);
558 #ifdef CONFIG_KMOD
559 		if (!parser && !request_module("%s", *types))
560 				parser = get_partition_parser(*types);
561 #endif
562 		if (!parser) {
563 			printk(KERN_NOTICE "%s partition parsing not available\n",
564 			       *types);
565 			continue;
566 		}
567 		ret = (*parser->parse_fn)(master, pparts, origin);
568 		if (ret > 0) {
569 			printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n",
570 			       ret, parser->name, master->name);
571 		}
572 		put_partition_parser(parser);
573 	}
574 	return ret;
575 }
576 
577 EXPORT_SYMBOL_GPL(parse_mtd_partitions);
578 EXPORT_SYMBOL_GPL(register_mtd_parser);
579 EXPORT_SYMBOL_GPL(deregister_mtd_parser);
580